22 Answers
22

Set/change your product name, I had this issue until I created a product name as same as project name.

The product name can be set in the Consent screen section of the Google Developers Console for your project. Look under APIs & auth in the left navigation and select Consent screen.
You need also to set your email address in the box above the product name.

Thankyou!! I was getting error ""Error: invalid_client. The OAuth client was not found." Wasted several hours today on this, but updated the product name just now and hey-presto, problem fixed. That error is so misleading.
– IanBFeb 25 '14 at 10:22

Unbelievable, even when clicking the "copy" button in the API console... You'd think Google's developers area would be whitespace sensitive!
– ReisclefDec 5 '16 at 11:00

Unbelievable as well here. Delete those extra spaces on both sides of the string. Then if after following all what has been said here and nothing still works, delete the app/project and re-create it again coz there could be caching issues.
– typelogicFeb 7 '17 at 19:15

1

Yeap, the issue still exists!!! Holy crap. I omitted one white space and didn't see it until recheck. Thanks.
– LukasSFeb 17 '17 at 1:27

1

darn! I saw the space at the end and removed it but did not check for the space in the beginning.
– sulabhJul 27 '17 at 9:30

"Throw away account" - not for Google, which tracks you and bundles all accounts you ever used to "associated accounts". And once Google bans one of the accounts - the whole bundle is blocked. Just search for "Google Developer account terminated" on Reddit.
– Alexander FarberDec 22 '18 at 21:08

In my case this turned out to be something else, namely my code used an environment variable that hadn't been set properly (and stupidly wasnt checked by my code). Setting it, recompiling assets, and restarting the app did the trick.

At Credentials
Accept requests from these HTTP referrers (web sites) (Optional)
Use asterisks for wildcards. If you leave this blank, requests will be accepted from any referrer. Be sure to add referrers before using this key in production.
Add . (star dot star) . It work fine for me

I accidentally had a value in the Client Secret part of the URL, but Google Credential does not need a Client Secret for Android OAuth 2 Client IDs. Simply leaving the value blank in the URL did the trick for me.

None of the following were my issue - I resolved this by opening an incognito window. Something was obviously being cached somewhere, no amount of changing auth client settings helped and there were never any trailing or leading spaces in config values.

Mine didn't work because I created it from a button from the documentation. I went again to the project and created another OAuthClientID. It worked. Yes, be careful about the extra spaces on right and left too.